Hey, I thought I'll send my very own plugin here. I like the idea of this website very much and I think it's directly addressing problems I'm struggling with.
I wanted to present you the Notification plugin. It can send the notifications for any WordPress action (like post published or user registered). The core supports the Email and Webhook but with simple API you can register your own.
Speaking of API... The plugin has been made as a module to the website I was building but I thought the idea is so nice it's worth extracting it. It was made super easy for developers to extend, so you can register new triggers or merge tags very fast.
Plugin link: https://wordpress.org/plugins/notification/